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    SubjectRe: [PATCH v2 01/16] hashtable: introduce a small and naive hashtable
    On 08/19/2012 04:16 PM, Mathieu Desnoyers wrote:
    > * Mathieu Desnoyers ( wrote:
    >> * Sasha Levin ( wrote:
    > [...]
    >>> +/**
    >>> + * hash_for_each_possible - iterate over all possible objects for a given key
    >>> + * @name: hashtable to iterate
    >>> + * @obj: the type * to use as a loop cursor for each bucket
    >>> + * @bits: bit count of hashing function of the hashtable
    >>> + * @node: the &struct list_head to use as a loop cursor for each bucket
    >>> + * @member: the name of the hlist_node within the struct
    >>> + * @key: the key of the objects to iterate over
    >>> + */
    >>> +#define hash_for_each_possible_size(name, obj, bits, node, member, key) \
    >>> + hlist_for_each_entry(obj, node, &name[hash_min(key, bits)], member)
    >> Second point: "for_each_possible" does not express the iteration scope.
    >> Citing WordNet: "possible adj 1: capable of happening or existing;" --
    >> which has nothing to do with iteration on duplicate keys within a hash
    >> table.
    >> I would recommend to rename "possible" to "duplicate", e.g.:
    >> hash_for_each_duplicate()
    >> which clearly says what is the scope of this iteration: duplicate keys.
    > OK, about this part: I now see that you iterate over all objects within
    > the same hash chain. I guess the description "iterate over all possible
    > objects for a given key" is misleading: it's not all objects with a
    > given key, but rather all objects hashing to the same bucket.
    > I understand that you don't want to build knowledge of the key
    > comparison function in the iterator (which makes sense for a simple hash
    > table).
    > By the way, the comment "@obj: the type * to use as a loop cursor for
    > each bucket" is also misleading: it's a loop cursor for each entry,
    > since you iterate on all nodes within single bucket. Same for "@node:
    > the &struct list_head to use as a loop cursor for each bucket".
    > So with these documentation changes applied, hash_for_each_possible
    > starts to make more sense, because it refers to entries that can
    > _possibly_ be a match (or not). Other options would be
    > hash_chain_for_each() or hash_bucket_for_each().

    I'd rather avoid starting to use chain/bucket since they're not used anywhere
    else (I've tried keeping internal hashing/bucketing opaque to the user).

    Otherwise makes sense, I'll improve the documentation as suggested. Thanks!

    > Thanks,
    > Mathieu

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      Last update: 2012-08-19 18:41    [W:0.025 / U:35.080 seconds]
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